Frank–Kasper (F-K) and quasicrystal phases were originally identified in metal alloys and only sporadically reported in soft materials. These unconventional sphere-packing schemes open up ...possibilities to design materials with different properties. The challenge in soft materials is how to correlate complex phases built from spheres with the tunable parameters of chemical composition and molecular architecture. Here, we report a complete sequence of various highly ordered mesophases by the self-assembly of specifically designed and synthesized giant surfactants, which are conjugates of hydrophilic polyhedral oligomeric silsesquioxane cages tethered with hydrophobic polystyrene tails. We show that the occurrence of these mesophases results from nanophase separation between the heads and tails and thus is critically dependent on molecular geometry. Variations in molecular geometry achieved by changing the number of tails from one to four not only shift compositional phase boundaries but also stabilize F-K and quasicrystal phases in regions where simple phases of spheroidal micelles are typically observed. These complex self-assembled nanostructures have been identified by combining X-ray scattering techniques and real-space electron microscopy images. Brownian dynamics simulations based on a simplified molecular model confirm the architecture-induced sequence of phases. Our results demonstrate the critical role of molecular architecture in dictating the formation of supramolecular crystals with “soft” spheroidal motifs and provide guidelines to the design of unconventional self-assembled nanostructures.
Based on polyvinylidene fluoride (PVDF) hollow fiber hydrophobic porous membrane, vacuum membrane distillation desalination test bench was built to study the effects of operating parameters such as ...temperature of feed solution, flow rate of feed solution, concentration of feed solution and vacuum degree on the performance of vacuum membrane distillation process. Experimental results showed that with an increase in the vacuum degree and temperature of the flux of membrane is increased. While with an increase in the concentration of feed solution of the flux of membrane is decreased and retention rate were essentially the same, with an increase in the flow rate of feed solution of he flux of membrane changed slowly (increase slightly). When temperature of the feed solution was 88°C, the flow rate of feed solution was 270cm/min, the vacuum degree was 0.081MPa, the concentration of feed solution was 5%, the flux of membrane was 14.1kg/ (m2.h), the retention rate was 99.8%, the electrical conductivity of fresh water was maintained at 12us/cm.
An integrated hydrogen and power co-generation system based on slurry-feed coal gasification and chemical looping hydrogen generation (CLH) was proposed with Shenhua coal as fuel and Fe2O3/MgAl2O4 as ...an oxygen carrier. The sensitivity analyses of the main units of the system were carried out respectively to optimize the parameters. The syngas can be converted completely in the fuel reactor, and both of the fuel reactor and steam reactor can maintain heat balance. The purity of hydrogen produced after water condensation is 100%. The energy and exergy analyses of the proposed system were studied. Pinch technology was adopted to get a reasonable design of the heat transfer network, and it is found pinch point appears at the hot side temperature of 224.7 °C. At the given status of the proposed system, the hydrogen yield is 1040.11 kg·h−1 and the CO2 capture rate is 94.56%. At the same time, its energy and exergy efficiencies are 46.21% and 47.22%, respectively. According to exergy analysis, the degree of exergy destruction is ranked. The gasifier unit has the most serious exergy destruction, followed by chemical looping hydrogen generation unit and the heat recovery steam generator unit.
•A hydrogen and power co-generation system is proposed and simulated.•Slurry-coal gasification is integrated with chemical looping hydrogen and combined cycle.•Assessing hydrogen production based on chemical looping conversion of fossil fuels.•Pure hydrogen can be achieved with high carbon capture efficiency through process integration.
•The multiphase flow over a spirally grooved hole nozzle was numerically investigated.•The spirally grooved hole led to partially spiral velocity field at the hole outlet.•The centrifugal force ...caused by spiral grooves promoted the breakup of liquid jets.•The spirally grooved hole nozzle yielded wider spreading angle and finer droplets.
To enhance fuel atomization for diesel engines, a spirally grooved hole (SGH) nozzle, in which several spiral arc grooves are set on the inner wall of tapered holes of a nozzle, forming flower-shaped cross sections, was designed. In this paper, the multi-phase flow inside and outside the SGH nozzle was calculated using a volume-of-fluid, large eddy simulation (VOF-LES) method to clarify the effects of spirally grooved hole on the cavitating flow and primary breakup characteristics for diesel nozzles. The calculation was carried out under injection pressure of 150 MPa and ambient pressure of 0.1 MPa for a SGH nozzle, and a non-grooved tapered hole (NSH) nozzle as a reference. Numerical results showed that the wall-guide effect of the spiral grooves in the hole of the SGH nozzle led to partially spiral flow of the fluid at the outer part of the nozzle hole, which in turn produced considerable centrifugal force on the liquid core, providing additional dynamics for the breakup of liquid jets besides aerodynamic effects. As a result, the deformation of the surface of the liquid column in a shorter distance from the outlet of the SGH nozzle were observed, and more ligaments and droplets were formed in the near-field, i.e., the breakup of the jet emerging from the SGH nozzle was substantially enhanced. The partially spiral flow also resulted in a largely wider near-field spreading angle and finer droplets than those of the NSH nozzle, with a penalty of 11.8% lower discharge coefficient.
To improve liquid atomization for pressure atomizer, a spirally grooved hole (SGH) nozzle was designed, which produces swirling flow inside the nozzle hole and thereby promotes the disturbance in ...liquid jets, enhancing breakup of liquid jets. In this paper, the optical visualization of the cavitating flow inside nozzles and primary breakup behaviors in the near-nozzle field for three scaled-up transparent nozzles, including two SGH nozzles with different spiral angles, and a non-spiral hole (NSH) nozzle, were performed to clarify the effects of the spirally grooved structures on in-nozzle cavitating flow and near-field fuel breakup. The results show that with an identical K-factor, the cavitation was largely restrained in the SGH nozzles, and the discharge coefficients of the SGH nozzles with spiral angles of 63° and 43° were approximately 13% and 25% lower than that of the NSH nozzle, respectively. Moreover, a liquid column was observed for each of the jets, surrounded with scattering droplets. And the SGH nozzle yields 9–10 times higher number density, 9%–10% smaller Sauter mean diameter of the droplets, and 4–7 times wider spreading angle than those of the NSH nozzle. These facts verified that the use of spirally grooved hole enhanced primary breakup of liquid jets.
•In- and out -nozzle multiphase flow of spirally grooved hole (SGH) nozzles was visualized.•The SGH nozzles restrained cavitation, and decreased discharge coefficients.•The SGH nozzles produced smaller droplets, wider spray.•The enhancing effects of SGH nozzles on jet breakup were experimentally verified.
Magnetic molecularly imprinted microcapsules (MMIMs) were synthesized by Pickering emulsion polymerization. In this work, an oil-in-water Pickering emulsion stabilized by halloysite nanotubes (HNTs) ...was first established in the presence of a few hydrophilic Fe sub(3)O sub(4) nanoparticles as magnetic separation carriers. The imprinting system was fabricated by radical polymerization and subsequent combination with functional and polymeric monomers in the oil phase. The formation mechanism of the Pickering emulsion and MMIMs is discussed in detail, and the as-prepared MMIMs are successfully evaluated as sorbents for the recognition of lambda -cyhalothrin. The results demonstrated that the MMIMs exhibited magnetic sensitivity (M sub(s) = 8.45 emu g super(-1)), a hollow structure, a semipermeable external surface and excellent robustness. The batch mode experiments proved that the imprinting effect synchronously improved the adsorption kinetics and equilibrium for the MMIMs. The selective recognition experiments also suggested high affinity and selectivity of MMIMs towards lambda -cyhalothrin over fenvalerate and diethyl phthalate.
The number of patients with hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB) has shown a significant upward trend in recent years. However, antiviral drugs are not very effective. ...Regulation of liver regeneration by traditional Chinese medicine is an important way to improve clinical efficacy. This randomized controlled trial assessed the efficacy and safety of DWYG in patients with HBeAg-negative CHB. Overall, 130 subjects were randomized to (A) DWYG 1.2 g three times daily (n = 44), (B) entecavir 0.5 mg/day (n = 43) in combination with DWYG or (C) entecavir 0.5 mg/day (n = 43). The liver histological response rate was assessed as the primary efficacy endpoint. The results showed that the liver histological response rate in the combination treatment group was significantly higher than that in the group with entecavir (71.43% versus 22.22%; P = 0.036) after 48 weeks of treatment. And the pathological progression rate of liver in the group with DWYG was significantly lower than that of the entecavir group during 228 weeks of follow-up (0% versus 60.00%; P = 0.019). No significant adverse events occurred during the study. In conclusion, treating HBeAg-negative CHB with DWYG is safe and effective to improve liver histological response.
According to the dissolution rate measurement method in Appendix X to 2010 Chinese Pharmacopoeia (Volume II) , the dissolution was measured in accordance with the mud cup method, the dissolution ...medium was 900 mL 2% degassed sodium dodecyl sulfate solution, the rotation speed 75 r/min, temperature (37 ± 0. According to the experiment results, Poriae Cutis total triterpenoids had an absorption peak at 260.7 CC , indicating that crude drug exists in the amorphous form; there was no peak at 260.7 °C for mixed excipients of liquid-solid compressed tablets, indicating that there is no mutual interaction between excipients and Poriae Cutis total triterpenoids; on the DSC curve of the liquid-solid compressed tablets, the absorption peak of main drug completely disappeared, indicating that the drug exists in the amorphous form in the liquid-solid powder. 4 Discussions In this experiment, we established the dissolution measurement method for Poriae Cutis total triterpenoids liquid-solid compressed tablets, fitted the cumulative dissolution-time curve for Poriae Cutis total triterpenoids liquid-solid compressed tablets and crude drug, carried out the variance analysis of the dissolution parameter tso and iD. At present, the application of liquid-solid compact technique is only reported in single component. ...we applied the liquidsolid compact technique into the extract of traditional Chinese medicine-Poriae Cutis total triterpenoids. DSC analysis indicates that the crystalline form of Poriae Cutis total triterpenoids disappears in the liquid-solid compressed system and exists in the form of molecule or amorphous form. ...the area at the dissolution is much larger than the traditional preparation; as a liquid carrier, NMP and PG have higher dissolution rate and certain suspension for Poriae Cutis total triterpenoids, and can be used as cosolvent; on the contact surface of powder of liquid-solid compressed tablets and dissolved medium, the diffused cosolvent increases the dissolution of drug; the liquid carrier also reduces the interfacial tension of drug particle and dissolved medium, increases the wettability of particle.
A systematic experimental approach is presented to quantitatively evaluate biodegradation rates in intact soil systems. Knowledge of bioremediation rates in intact soil systems is important for ...evaluating the efficacy of in-situ biodegradation and approaches for enhancing degradation rates. The approach involves three types of soil bioreactors: slurry, wafer, and porous tube. In the soil slurry reactor, biodegradation occurs in the aqueous phase by suspended and soil-immobilized microorganisms. In the soil wafer reactor, diffusivity of contaminant in the soil matrix controls the biodegradation rate. In the porous tube reactor, oxygen limitations occur inside the tube due to diffusional resistances, and oxygen consumption occurs due to biodegradation. Measurement of cumulative oxygen uptake in soil slurry, wafer, and porous tube reactors are used to determine biokinetics and transport parameters. It is shown that biodegradation rates in intact soil systems are slower than in soil slurry reactors. Furthermore, soil tube reactors in conjunction with respirometry can be used to assess bioremediation rates in intact soil systems.
The CuS semiconductor photocatalysts with the spherical morphology have been synthesized through the solvothermal method. The as-prepared photocatalysts have been characterized by scanning electron ...microscopy (SEM), UV-vis absorption (UV-vis). The photo-degradation experiments of the the as-prepared photocatalysts were performed in the visible light illumination and the methylene blue was choose as the wastewater pollutants. Particularly, the CuS semiconductor photocatalysts shows the highest degradation ratio (70%) of methylene blue under the visible light irradiation.
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